Development of Advanced Aerosol Instrumentation

据世界卫生组织称，2016年，室外和室内空气污染估计在全球每年造成约720万人过早死亡，主要是由于暴露于可导致心血管和呼吸系统疾病以及癌症的颗粒物（PM）。空气污染是世界上导致疾病和过早死亡的最大环境因素。空气污染造成的死亡人数超过高钠饮食、肥胖、艾滋病、结核病、疟疾、酒精、烟草、道路交通事故、儿童和孕产妇营养不良、战争和一切形式的暴力。加拿大政府估计，每年有14,400名加拿大人死于空气污染的影响，空气污染影响的年度经济成本约为80亿美元。此外，政府间气候变化专门委员会指出，煤烟（含碳颗粒物）在全球气候强迫中起着重要作用，气候变化的影响“包括生态系统的改变、粮食生产和供水的中断、基础设施和住区的破坏、发病率和死亡率”。PM的负面影响可以通过技术进步和法规来减少。然而，如果没有量化PM排放和了解其性质的工具，这些减少是不可能的。我研究的主要重点是开发新的气溶胶仪器和技术，以量化排放并了解PM对健康和气候的影响，以便制定适当的环境政策和法规。这项发现基金的目标是在两个重要的研究领域开发和使用新的分析技术，即：低成本的PM传感器校准和煤烟对气候的影响。i)低成本的PM传感器校准-鉴于空气污染是一个主要的全球性问题，最近在低成本PM传感器的开发方面出现了爆炸式增长。这些系统用于建筑物通风（过滤）控制，监测城市地区的PM，工作场所危害和暴露识别以及发动机排放监测。然而，低成本的PM传感器技术仍处于起步阶段，传感器开发商正在使用间接测量技术来测量颗粒的质量。因此，需要一个系统来校准或表征这些传感器。本文研究了两种校准传感器的方法。ii)涂覆烟尘的混合状态和光学性质——气候模式的一个很大的不确定性来源是由于大气中涂覆烟尘的有机物质。烟灰涂层对烟灰光学性能产生两种相互竞争的影响。由于折射增强（加剧气候变暖），涂层可能导致“透镜”效应，和/或由于表面张力（减缓变暖），可能导致煤烟“坍塌”。本建议使用新颖的仪器来测量和了解这些影响的大小，并了解这些影响在大气中的相对重要性。

According to the World Health Organization, outdoor and indoor air pollution was estimated to cause ~7.2 million premature deaths worldwide per year in 2016, primarily due to exposure to particulate matter (PM), which causes cardiovascular and respiratory disease, and cancers. Air pollution is the largest environmental cause of disease and premature death in the world. Air pollution is responsible for more deaths than a high-sodium diet, obesity, AIDS, tuberculosis, malaria, alcohol, tobacco, road accidents, child and maternal malnutrition, or war and all forms of violence. The Canadian Government estimates 14,400 Canadians die from the effects of air pollution each year and the annual economic cost of the effects of air pollution is ~$8 billion. Furthermore, the Intergovernmental Panel on Climate Change states that soot (carbonaceous PM) plays a major role in global climate forcing and the impacts of climate change "include alteration of ecosystems, disruption of food production and water supply, damage to infrastructure and settlements, morbidity and mortality". The negative effects of PM can be reduced through technological advancements and regulations. However, these reductions are not possible without instruments to quantify PM emissions and understand their properties. The primary focus of my research has been developing novel aerosol instruments and techniques to quantify emissions and understand the effect PM has on health and climate so that appropriate environmental policies and regulations can be developed. The goals of this Discovery Grant are to develop and use new analytical techniques in two important research areas, namely: low-cost PM sensor calibration and the climate impact of soot. i) Low-cost PM sensor calibration - Given that air pollution is a major global problem, there has been a recent explosion in the development of low-cost PM sensors. These systems are used for building ventilation (filtration) control, monitoring PM in urban areas, workplace hazard and exposure identification, and engine emissions monitoring. However, low-cost PM sensor technology is still in its infancy and sensor developers are using indirect measurement techniques to measure the mass of the particles. Thus, a system is necessary to calibrate or characterization these sensors. This proposal investigates two methods for calibrating these sensors. ii) Mixing state and optical properties of coated soot - One large source of uncertainty in climate models is due to organic material coating soot in the atmosphere. Coatings on soot create two competing effects on soot optical properties. The coating may cause a `lensing' effect due to enhanced refraction (enhancing climate warming) and/or may cause the soot to `collapse' due to surface tension (decreasing warming). This proposal uses novel instrumentation to measure and understand the magnitude of these effects and understand the relative importance of these effects in the atmosphere.